Abstract: Biomarkers for neurodegenerative diseases should reflect the central
pathogenic processes of the diseases. The field of clinical proteomics is
especially well suited for discovery of biomarkers in cerebrospinal fluid
(CSF), which reflects the proteins in the brain under healthy conditions as
well as in several neurodegenerative diseases. Known proteins involved in the
pathology of neurodegenerative diseases are, respectively, normal tau protein,
β-amyloid (1-42), synaptic proteins, amyloid precursor protein (APP),
apolipoprotein E (apoE), which previously have been studied by protein
immunoassays. The objective of this paper was to summarize results from
proteomic studies of differential protein patterns in neurodegenerative
diseases with focus on Alzheimer's disease (AD). Today, discrimination of AD
from controls and from other neurological diseases has been improved by
simultaneous analysis of both β-amyloid (1-42), total-tau, and
phosphorylated tau, where a combination of low levels of CSF-β-amyloid
1-42 and high levels of CSF-tau and CSF-phospho-tau is associated with an AD
diagnosis. Detection of new biomarkers will further strengthen diagnosis and
provide useful information in drug trials. The combination of immunoassays and
proteomic methods show that the CSF proteins express differential protein
patterns in AD, FTD, and PD patients, which reflect divergent underlying
pathophysiological mechanisms and neuropathological changes in these
diseases.
